As a crucial component of the Earth’s climate system,Antarctic sea ice has demonstrated significant variability over the satellite era.Here,we identify a remarkable decadal transition in the total Antarctic Sea Ice E...As a crucial component of the Earth’s climate system,Antarctic sea ice has demonstrated significant variability over the satellite era.Here,we identify a remarkable decadal transition in the total Antarctic Sea Ice Extent(SIE).The stage from 1979 to 2006 is characterized by high-frequency(i.e.,seasonal to interannual)temporal variability in SIE and zonal asymmetry in Sea Ice Concentration(SIC),which is primarily under the control of the Amundsen Sea Low(ASL).After 2007,however,sea ice changes exhibit a more spatially homogeneous pattern in SIC and a more temporally long-lasting mode in SIE.Further analysis reveals that sea ice-ocean interaction plays a major role in the low-frequency(i.e.,multiannual)variability of Antarctic sea ice from 2007−22.The related physical process is inferred to manifest as a strong coupling between the surface and the subsurface ocean layers,involving enhanced vertical convection and the downward delivery of the surface anomalies related to ice melting and freezing processes,thus maintaining the SIE anomalies for a longer time.Furthermore,this process mainly occurs in the Amundsen-Bellingshausen Sea(ABS)sector,and the weakened subsurface ocean stratification is the key factor triggering the coupling process in this region.We find that the Circumpolar Deep Water(CDW)over the ABS sector continued to shoal before 2007 and remained stable thereafter.It is speculated that the shoaling of the CDW may be a possible driver leading to the weakening of the subsurface stratification.展开更多
El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation an...El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further investigation.To investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 models.The results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the future.The higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in variability.Carbon flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through temperature.This occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.展开更多
During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the s...During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis results.To elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget analysis.The findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern Pacific.This increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective instability.Such a process is pivotal in amplifying intraseasonal convection anomalies.The observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.展开更多
Maize is an important source of calories and protein in human lives in many countries of the world and is the main staple food in Africa, particularly in eastern Africa. In the Sudan, the low yield of maize was mainly...Maize is an important source of calories and protein in human lives in many countries of the world and is the main staple food in Africa, particularly in eastern Africa. In the Sudan, the low yield of maize was mainly due to the use of low yielding landraces. It is necessary to carry out breeding programs that deal with the production of high yielding, adaptable new varieties. Therefore, this study aimed to estimate genetic variability, heritability, genotypic performance and interrelationships among the traits. Ten maize genotypes evaluated at White Nile Research Station Farm, Kosti, of the Agricultural Research Corporation (ARC), Wad Medani Sudan were planted in a randomized complete block design with three replications during the two seasons of 2021 and 2022. Most evaluated genotypes exhibited a wide and significant variation in the 11 measured traits. Genotypic coefficient of variation and genetic advance were recorded for days to 50% tasseling, ear diameter (cm), number of grains per row and grain yield (t/ha) in both seasons. High heritability and genetic advance were recorded for grain yield, ear length, ear height, plant height, number of rows per ear, ear weight, days to 50% tasseling, 100-grain weight and days to 50% silking. Moreover, there was a highly significant and positive correlation of grain yield with number of rows per ear (r = 0.479), ear length (r = 0.381), 100-grain weight (r = 0.344) and days to 50% tasseling (r = 0.214). The highest yielding five genotypes across the seasons were TZCOM1/ZDPSYN (4.2 t/ha), EEPVAH-3 (4.2 t/ha), F2TWLY131228 (4.1 t/ha), PVA SYN6F2 (3.9 t/ha) and EEPVAH-9 (3.8 t/ha) these were needed to check the adaptability, stability and to test major maize growing areas to make sound recommendations for release.展开更多
The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(E...The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole(IOD)events.The detailed processes of ENSO and/or IOD induced anomalies impacting on the ITF,however,are still not clear.In this study,this issue is investigated through causal relation,statistical,and dynamical analyses based on satellite observation.The results show that the driven mechanisms of ENSO on the ITF include two aspects.Firstly,the ENSO related wind field anomalies driven anomalous cyclonic ocean circulation in the western Pacific,and off equatorial upwelling Rossby waves propagating westward to arrive at the western boundary of the Pacific,both tend to induce negative sea surface height anomalies(SSHA)in the western Pacific,favoring ITF reduction since the develop of the El Niño through the following year.Secondly,the ENSO events modulate equatorial Indian Ocean zonal winds through Walker Circulation,which in turn trigger eastward propagating upwelling Kelvin waves and westward propagating downwelling Rossby waves.The Rossby waves are reflected into downwelling Kelvin waves,which then propagate eastward along the equator and the Sumatra-Java coast in the Indian Ocean.As a result,the wave dynamics tend to generate negative(positive)SSHA in the eastern Indian Ocean,and thus enhance(reduce)the ITF transport with time lag of 0-6 months(9-12 months),respectively.Under the IOD condition,the wave dynamics also tend to enhance the ITF in the positive IOD year,and reduce the ITF in the following year.展开更多
Varietal deficiencies of upland rice lead to a low paddy grain yield. The aim of this study was to mutagenesis upland rice varieties to improve their agronomic performance. Seeds of varieties FKR45N and FKR47N were th...Varietal deficiencies of upland rice lead to a low paddy grain yield. The aim of this study was to mutagenesis upland rice varieties to improve their agronomic performance. Seeds of varieties FKR45N and FKR47N were therefore irradiated with doses 300, 350 and 400 Gy. The irradiated seeds were sown and the panicles of the M1 plants were individually harvested, and then were advanced to M4 using the “one panicle - one progeny” method. The agronomic performance of M4 lines was compared to that of their parent. The gamma ray mutagenesis has induced significant variability in five yield components, i.e., plant height, main panicle length, total numbers of tillers and productive tillers and paddy grain yield between mutant lines. The highest variabilities were shown for the total number of tillers and the number of productive tillers as well as FKR45N (CV% = 40 % and 36%) and FKR47N (CV% = 31% and 30%) mutant lines. Principal component analysis led to rank the mutant lines from each variety in three clusters. The Pearson correlation showed that the paddy grain yield was significantly and positively correlated with the number of productive tillers (r = 0.61) and plant height (r = 0.66) for FKR47N mutant lines, and these correlation coefficients were r = 0.52 and r = 0.51 for FKR45N mutant lines, respectively. Gamma-ray irradiation also induced an earliness of 50% flowering of 62 days after sowing (DAS) in two FKR45N mutant lines and 67 DAS in one of KR47N mutant lines. The paddy grain yield was improved by 120% and 20% in two FKR45N and FKR47N mutant lines, respectively. A dwarf FKR45N mutant line with an early flowering of 67 DAS and a paddy grain yield (2.34 t ha−1) was generated. These results suggested that any positive increase in the six quantitative traits will increase the paddy grain yield.展开更多
Introduction:Heart rate variability(HRV),defined as fluctuations in the time intervals between successive heartbeats,was generated by the sinoatrial node and modulated by the autonomic nervous system(ANS).HRV emerged ...Introduction:Heart rate variability(HRV),defined as fluctuations in the time intervals between successive heartbeats,was generated by the sinoatrial node and modulated by the autonomic nervous system(ANS).HRV emerged as a prognostic marker in chronic heart failure(CHF),particularly for mortality risk assessment in Western countries.This study aimed to evaluate the utility of HRV measurement in the follow-up of CHF patients in a sub-Saharan African context.Methods:We conducted a cross-sectional,descriptive,and analytical study during six months,in the cardiology departments of the YaoundéGeneral Hospital(HGY)and the YaoundéCentral Hospital(HCY).Eligible participants were adults with a confirmed diagnosis of CHF based on clinical,echocardiographic and electrocardiographic criteria,who had been on treatment for at least three months and provided informed consent.Exclusion criteria included atrial disease,non-sinus rhythm(atrial fibrillation,atrial flutter),loss to follow-up,and death.Consecutive sampling was applied.HRV recordings were obtained twice at a two-month interval using a Polar H10^(®)heart rate monitor connected via Bluetooth to the Elite HRV application installed on an iPhone 12 Pro Max.SDNN was the standard deviation of all normal-to-normal(NN)intervals,and RMSSD was Root Mean Square of Successive Differences.HF(High Frequency,0.15-0.40 Hz)corresponds to respiratory sinus arrhythmia;R-R intervals were recorded at rest for 5 minutes.Treat ment adherence was assessed and its relationship to HRV was explored.Data were entered using CS Pro^(®)7.0 and analyzed with SPSS^(®)23.Results:Thirtyone patients were included,with a median age of 64 years;women accounted for 54.8%of the sample.The most prevalent cardiovascular risk factors were dyslipidemia(38.7%)and alcohol consumption(34.6%).The leading etiologies of CHF were hypertensive cardiomyopathy and dilated cardiomyopathy,each representing 54.8%of cases.Left ventricular failure was present in 74.2%,and 61.3%had a left ventricular ejection fraction(LVEF)<40%.The most commonly prescribed medications were ACE inhibitors(80.6%),beta-blockers(77.4%),and loop diuretics(77.4%).Non-adherence to treatment was reported in 45.2%(14/31)of participants.Patients with good adherence demonstrated significantly higher HRV indices at both time points,including SDNN[46.7(37.3-54.4)ms;p<0.050],RMSSD[58.6(49.5-78.9)ms;p<0.010],and HF power[708.2(417.2-1020.0)ms^(2);p=0.040].Factors associated with HRV impairment found a borderline association with BMI:overweight/obese patients tended to have higher odds of HRV impairment(OR=1.7,95%CI:0.4-7.4,p=0.052);age≤60 years(OR=0.8,95%CI:0.4-8.1,p<0.044)and Beta-blocker(OR=0.5,95%CI:0.1-2.5,p=0.030)use was associated with a lower risk of HRV alteration.Treatment with good adherence showed a significant association linked to a lower risk of HRV impairment(OR=0.2,95%CI:0.0-1.3).Conclusion:This study confirms the potential of HRV as a complementary tool for the follow-up of CHF patients.HRV indices,particularly regarding young age,good weight and combined with treatment adherence assessment,may provide a cost-effective,non-invasive method to improve CHF management in resource-limited settings.展开更多
Utilizing the Standardized Precipitation Evapotranspiration Index(SPEI)and ERA5 reanalysis data,this study investigates the variability of spring drought in southern China from 1979 to 2022 and its associated drivers....Utilizing the Standardized Precipitation Evapotranspiration Index(SPEI)and ERA5 reanalysis data,this study investigates the variability of spring drought in southern China from 1979 to 2022 and its associated drivers.The results indicate that southern China experienced interdecadal changes in SPEI over the past several decades,which can be concluded that drought severity intensified from 1979 to 2010,whereas a transition shift towards increased wetness occurred from 2010 to 2022.The first Empirical Orthogonal Function(EOF1)mode of SPEI variability in southern China accounts for 44.37%of the total variance,reflecting a uniform variation of SPEI across the region.In contrast,the second Empirical Orthogonal Function(EOF2),which explains 24.41%of the total variance,reveals a west-east dipole pattern in SPEI variability.Further analysis indicates that the positive phase of EOF1 is primarily driven by warm sea surface temperature anomalies(SSTAs)in the tropical eastern Pacific.These anomalies induce an anomalous anticyclone over the Philippine Sea,enhancing water vapor transport to southern China during spring.The positive phase of EOF2 is jointly influenced by warm SSTAs in the tropical Indian Ocean and the central Pacific;the latter induces anticyclonic anomalies over the Philippine Sea,which enhance water vapor transport from the western Pacific and increase precipitation in the eastern part of southern China.However,the warm SSTAs in the tropical Indian Ocean trigger an anomalous anticyclone over South Asia,inhibiting water vapor transport from the Bay of Bengal to the western part of southern China and thus reducing precipitation there.展开更多
In this article,Deng and Song showed compelling evidence on the connection between heart rate variability(HRV)alterations and cancer in 127 cancer patients compared with healthy reference individuals,highlighting auto...In this article,Deng and Song showed compelling evidence on the connection between heart rate variability(HRV)alterations and cancer in 127 cancer patients compared with healthy reference individuals,highlighting autonomic nervous system dysfunction as a significant physiological manifestation in cancer patients.We discussed that the reduced HRV may be associated with cancer treatments,e.g.,operation,chemotherapy and pain control and psychological response such as depression and anxiety related to the affected cancer.A management such as medicine to mood disturbances related to cancer has been shown a benefit to improve HRV in cancer patients.展开更多
This research employs micro-CT scanning technology to analyze the porosity,pore fractal dimension,and spatial variability of sandstone preheated to 600℃ and subsequently cooled in water at varying temperatures(20℃,6...This research employs micro-CT scanning technology to analyze the porosity,pore fractal dimension,and spatial variability of sandstone preheated to 600℃ and subsequently cooled in water at varying temperatures(20℃,60℃,100℃).The study investigates the mechanisms by which various factors influence thermal shock damage,focusing on the effects of cooling water temperature and the boiling phase transition.The objective is to develop a method for characterizing thermal shock damage that considers spatial variability.The findings indicate that thermal shock damage is limited to a shallow depth beneath the surface,with increased severity near the surface.The boiling phase transition significantly enhances the convective heat transfer coefficient,resulting in substantially higher thermal shock damage when cooled with 100℃ boiling water compared to 20℃ and 60℃ water.Furthermore,for the entire specimen,heating damage exceeds thermal shock damage,and the influence of thermal shock diminishes as specimen size increases.This study addresses the limitations of traditional methods for assessing thermal shock damage that disregard spatial variability and provides practical guidance for engineering projects to manage thermal shock damage more effectively.展开更多
Purpose:To explore the clinical value of Electromyography(EMG)and Heart Rate Variability(HRV)in the diagnosis of early DPN and provide the basis for early diagnosis,treatment,and prevention of DPN.Methods:105 patients...Purpose:To explore the clinical value of Electromyography(EMG)and Heart Rate Variability(HRV)in the diagnosis of early DPN and provide the basis for early diagnosis,treatment,and prevention of DPN.Methods:105 patients with type 2 diabetes mellitus(T2DM)in the Changji People’s Hospital were treated from January 2023 to December 2023.They were stratifi ed into DPN-symptomatic(DPN group,n=55)and DPN-asymptomatic(NDPN group,n=50)cohorts based on the presence or absence of clinically confi rmed diabetic peripheral neuropathy.The clinical biochemical indicators,nerve electromyography,and HRV parameters were obtained from electronic medical records,and diff erences in detection results were compared between the two groups.Logistic regression was applied to analyze the infl uencing factors of DPN in diabetes patients.The receiver operating characteristic(ROC)curve was applied to analyze the diagnostic value of EMG combined with other parameters for DPN.Results:From the results of the general information,diabetes duration,glycosylated hemoglobin(HbA1c),low-density lipoprotein cholesterol(LDL-C),total cholesterol(TC)and FBG in the DPN group were significantly differences compared with the NDPN group(p<0.05).There were no statistically significant differences in gender,age years,uric acid,and other general data(p>0.05).Compared with the NDPN group,the motor nerve conduction velocity(MNCV),sensory nerve conduction velocity(SNCV)of the ulnar nerve,median nerve,and tibial nerve in the DPN group were statistically signifi cant(p>0.05).The DPN group had higher average F wave latency and H wave latency in the tested nerve,with statistical signifi cance(p<0.05).HRV parameters decreased signifi cantly(SDNN,rMSSD,PNN50,and SDANN,all p<0.05).ROC analysis showed that the area under the ROC curve(AUC)of the combined diagnosis of DPN by duration of diabetes,HbA1c,EMG,and HRV was 0.897,the accuracy was 82.86%,the sensitivity was 78.00%,and the specifi city was 87.27%.The AUC of the combined diagnosis of the four parameters for DPN was signifi cantly higher than that of each alone(p<0.05).Conclusion:The combination of EMG and HRV has a high value in the assessment of DPN and can be used for early assessment of the extent of the lesion.展开更多
In recent years,the water level in the Mekong Delta(MD)has undergone changes,attributed to the impacts of anthropogenic activities and climate change.Declining water levels have had implications for various aspects of...In recent years,the water level in the Mekong Delta(MD)has undergone changes,attributed to the impacts of anthropogenic activities and climate change.Declining water levels have had implications for various aspects of life and aquatic ecosystems in the lower basin water bodies.Analyzing long-term trends in rainfall and water levels is crucial for enhancing our understanding.This study aims to examine the evolving patterns of water level and rainfall in the region.Data on water levels and rainfall from observation stations were gathered from the National Center for Hydrometeorological Forecasting,Vietnam,spanning from 2000 to 2014.The assessment of homogeneity and identification of trend changes were conducted using the Standard Normal Homogeneity Test(SNHT)and the Mann-Kendall test.The results indicate that changes in water levels at the Tan Chau and Chau Doc stations have been observed since 2010 due to the operation of flow-regulating structures in the upper Mekong River.Following the commencement of upstream dam operations,the water level at the headwater stations of the Mekong River has been higher than the long-term average during the dry season and lower than the average during the flood season.The study findings highlight the influence of altered rainfall patterns under the impact of climate variability(ICC)on water level trends in the study area.While rainfall plays a significant role in increasing water levels during the flood season,the operation of hydropower dams(UHDs)stands out as the primary factor driving water level reductions in the study area.展开更多
BACKGROUND Heart rate variability(HRV)represents efferent vagus nerve activity,which is suggested to be related to fundamental mechanisms of tumorigenesis and to be a predictor of prognosis in various cancers.Therefor...BACKGROUND Heart rate variability(HRV)represents efferent vagus nerve activity,which is suggested to be related to fundamental mechanisms of tumorigenesis and to be a predictor of prognosis in various cancers.Therefore,this study hypothesized that HRV monitoring could predict perioperative complication(PC)in colorectal cancer(CRC)patients.AIM To investigate the prognostic value of HRV in hospitalized CRC patients.METHODS The observational studies included 87 patients who underwent CRC surgical procedures under enhanced recovery after surgery programs in a first-class hospital.The HRV parameters were compared between the PC group and the non PC(NPC)group from preoperative day 1 to postoperative day(Pod)3.In addition,inflammatory biomarkers and nutritional indicators were also analyzed.RESULTS The complication rate was 14.9%.HRV was markedly abnormal after surgery,especially in the PC group.The frequency-domain parameters(including pNN50)and time-domain parameters[including high-frequency(HF)]of HRV were significantly different between the two groups postoperatively.The pNN50 was significantly greater at Pod1 in the PC group than that in the NPC group and returned to baseline at Pod2,suggesting that patients with complications exhibited autonomic nerve dysfunction in the early postoperative period.In the PC group,HFs were also enhanced from Pod1 and were significantly higher than in the NPC group;inflammatory biomarkers were significantly elevated at Pod2 and Pod3;the levels of nutritional indicators were significantly lower at Pod1 and Pod2;and the white blood cell count was slightly elevated at Pod3.CONCLUSION HRV is independently associated with postoperative complications in patients with CRC.Abnormal HRV could predicted an increased risk of postoperative complications in CRC patients.Continuous HRV could be used to monitor complications in patients with CRC during the perioperative period.展开更多
Since the mid-20th century,the Mongolian Plateau(MP)has experienced decadal droughts coupled with extreme heatwaves,severely affecting regional ecology and social development.However,the mechanisms behind these decada...Since the mid-20th century,the Mongolian Plateau(MP)has experienced decadal droughts coupled with extreme heatwaves,severely affecting regional ecology and social development.However,the mechanisms behind these decadalscale compound heatwavedrought events remain debated.Here,using reconstructions and simulations from the Community Earth System Model Last Millennium Ensemble,we demonstrate that,over the last millennium,decadal droughts on the MP occurred under both warm and cold conditions,differing from recent compound heatwavedrought events.We found that by examining temperature changes during these drought periods,the distinct influences of external forcings and internal variability can be simply and effectively distinguished.Specifically,colddry events were primarily driven by volcanic eruptions that weakened the East Asian summer monsoon and midlatitude westerlies,reducing moisture transport to the MP.In contrast,warmdry events were predominantly induced by internal variability,notably the negative phase of the Atlantic Multidecadal Oscillation and the expansion of the Barents Sea ice extent.The recent extreme compound event was probably influenced by the combined effects of anthropogenic forcings and internal variability.These findings deepen our understanding of how external forcings and internal variability affect decadal drought events on the MP and highlight that recent compound events are unprecedented in the context of the last millennium.展开更多
Extensive flooding swept across large areas of Central Asia,mainly over Kazakhstan and southwestern Russia,from late March to April 2024.It was reported to be the worst flooding in the area in the past 70 years and ca...Extensive flooding swept across large areas of Central Asia,mainly over Kazakhstan and southwestern Russia,from late March to April 2024.It was reported to be the worst flooding in the area in the past 70 years and caused widespread devastation to society and infrastructure.However,the drivers of this record-breaking flood remain unexplored.Here,we show that the record-breaking floods were contributed by both long-term climate warming and interannual variability,with multiple climatic drivers at play across the synoptic to seasonal timescales.First,the heavy snowmelt in March 2024 was associated with above-normal preceding winter snow accumulation.Second,extreme rainfall was at a record-high during March 2024,in line with its increasing trend under climate warming.Third,the snowmelt and extreme rainfall in March were compounded by record-high soil moisture conditions in the preceding winter,which was a result of interannual variability and related to excessive winter rainfall over Central Asia.As climate warming continues,the interplay between the increasing trend of extreme rainfall,interannual variations in soil moisture pre-conditions,as well as shifting timing and magnitudes of spring snowmelt,will further increase and complicate spring flooding risks.This is a growing and widespread challenge for the mid-to high-latitude regions.展开更多
Climate variability significantly impacts agricultural water resources,particularly in regions like Vietnam's Plain of Reeds that heavily utilize rain-fed conditions.This study employs the FAO-AquaCrop model to es...Climate variability significantly impacts agricultural water resources,particularly in regions like Vietnam's Plain of Reeds that heavily utilize rain-fed conditions.This study employs the FAO-AquaCrop model to estimate current and future irrigation water needs for rice cultivation in this critical subregion,aiming to identify optimal sowing schedules(OSS)that enhance rainwater utilization and reduce irrigation dependency.The model was driven by current climate data and future projections(2041-2070 and 2071-2099)derived from downscaled Global Circulation Models under RCP4.5 and RCP8.5 scenarios.The AquaCrop model demonstrated robust performance during validation and calibration,with d-values(0.82-0.93)and R²values(0.85-0.92)indicating strong predictive accuracy for rice yield.Simulation results for efficient irrigation water potential(IWP)under RCP4.5 revealed that strategic shifts in sowing dates can substantially alter water requirements;for instance,advancing the winter-spring sowing to December 5th decreased IWP by 15.6%in the 2041-2070 period,while delaying summer-autumn crop sowing to April 20th increased IWP by 48.6%due to greater reliance on irrigation as rainfall patterns shift.Similar dynamic responses were observed for the 2071-2099 period and for autumn-winter crops.These findings underscore that AquaCrop modeling can effectively predict future irrigation needs and that adjusting cultivation calendars presents a viable,low-cost adaptation strategy.This approach allows farmers in the Plain of Reeds to optimize rainwater use,thereby reducing dependency on supplementary irrigation and mitigating the adverse impacts of climate variability,contributing to more sustainable agricultural water management.展开更多
Sandy cobble soil exhibits pronounced heterogeneity.The assessment of the uncertainty surrounding its properties is crucial for the analysis of settlement characteristics resulting from volume loss during shield tunne...Sandy cobble soil exhibits pronounced heterogeneity.The assessment of the uncertainty surrounding its properties is crucial for the analysis of settlement characteristics resulting from volume loss during shield tunnelling.In this study,a series of probabilistic analyses of surface and subsurface settlements was conducted considering the spatial variability of the friction angle and reference stiffness modulus,under different volumetric block proportions(Pv)and tunnel volume loss rates(ηt).The non-intrusive random finite difference method was used to investigate the probabilistic characteristics of maximum surface settlement,width of subsurface settlement trough,maximum subsurface settlement,and subsurface soil volume loss rate through Monte Carlo simulations.Additionally,a comparison between stochastic and deterministic analysis results is presented to underscore the significance of probabilistic analysis.Parametric analyses were subsequently conducted to investigate the impacts of the key input parameters in random fields on the settlement characteristics.The results indicate that scenarios with higher Pv or greaterηt result in a higher dispersion of stochastic analysis results.Neglecting the spatial variability of soil properties and relying solely on the mean values of material parameters for deterministic analysis may result in an underestimation of surface and subsurface settlements.From a probabilistic perspective,deterministic analysis alone may prove inadequate in accurately capturing the volumetric deformation mode of the soil above the tunnel crown,potentially affecting the prediction of subsurface settlement.展开更多
Siberian taimen Hucho taimen(Pallas,1773)is a broadly distributed and popular sport fish with high economic value.However,low abundance and hard-to-reach habitat make the Siberian taimen a relatively understudied spec...Siberian taimen Hucho taimen(Pallas,1773)is a broadly distributed and popular sport fish with high economic value.However,low abundance and hard-to-reach habitat make the Siberian taimen a relatively understudied species.Here we describe the morphological variability of two size groups of Siberian taimen juveniles from the eastern(Amur River basin)and western(Kama River basin)parts of the species distribution.The largest morphological differentiation of Siberian taimen juveniles was observed at the inter-basin level.In the Amur River basin,Siberian taimen juveniles also differed morphologically even at sites located at a distance of 20 km from each other,which may be explained by a small home-range inhabitation of juveniles leading to the formation of their morphotype determined by local environmental conditions.The pattern of allometry varies in taimen from different rivers,which could be related to the ontogenetic shift of ecological niches and the level of heterogeneity of the river environment.展开更多
El Niño is frequently followed by La Niña,while La Niña tends to sustain into the next year or even longer,exhibiting a notable phase transition asymmetry(TA)of El Niño-Southern Oscillation(ENSO).T...El Niño is frequently followed by La Niña,while La Niña tends to sustain into the next year or even longer,exhibiting a notable phase transition asymmetry(TA)of El Niño-Southern Oscillation(ENSO).This study explores the potential influences of tropical Indian Ocean(TIO)decadal variability on TA based on a comparative analysis of the relationship between the TIO sea surface temperature anomalies(SSTA)and ENSO during different periods.Generally,the TIO SSTA strengthened TA before the 1980s,corresponding to a highly positive relationship between the whole TIO SSTA and ENSO.However,the weakening effect was exhibited after the 1980s when the correlation diminished.After the late 1990s,ENSO was only positively correlated with western TIO,with the westerly exhibit of the SSTA center leading to smaller impacts on TA.Moreover,TIO SSTA tends to weaken TA by promoting the transition efficiency of La Niña,while bringing little effect on that of El Niño.Physically,compared to the mid-1970s,TIO SSTA triggered westerly wind anomalies during the autumn and winter of the La Niña development phase in the central equatorial Pacific in the late 1990s,which sped up the decay of La Niña.It then regenerated westerly anomalies in the following winter,facilitating the development of El Niño.This study quantifies the impact of the TIO SSTA on TA in seasonal signals and investigates the decadal variability of such influence,aiming to further understand phase transition asymmetry and offer valuable insights for the prediction of multi-year La Niña.展开更多
This study characterizes the instrumental record of California climate for the last 170 years.Our goal is to look for hydrologic variability at decadal and longer time scales that would be consistent with paleoclimate...This study characterizes the instrumental record of California climate for the last 170 years.Our goal is to look for hydrologic variability at decadal and longer time scales that would be consistent with paleoclimate estimates of hydrologic variability in California for the last 3000 years.Our study focuses on meteorological summaries of annual precipitation and temperature.The precipitation records go back as far as 1850;the temperature records go back as far as 1880.California hydrologic records show strong variability at the interannual level due to ENSO forcing.They also all show a strong decadal(∼14 yr)cyclicity and evidence for multi-decadal to centennial variability that is consistent with California paleoclimate studies.California temperature records show a long-term warming of 5°F-6°F(2.8°C-3.4°C)associated with global warming,but there is no evidence for a similar long-term trend in hydrologic variability.Long-term Pacific Ocean variability adjacent to central and northern California,Pacific Decadal Oscillation(PDO)and North Pacific Gyre Oscillation(NPGO),show a similar decadal to centennial pattern of variability that we associate with our long-term hydrologic variability.The positive phase of the NPGO and the negative phase of the PDO are associated with the decadal scale(∼14 yr)dry cycles in California for the last 70 years.展开更多
基金supported by the National Natural Science Foundation China(Grant No.42176222).
文摘As a crucial component of the Earth’s climate system,Antarctic sea ice has demonstrated significant variability over the satellite era.Here,we identify a remarkable decadal transition in the total Antarctic Sea Ice Extent(SIE).The stage from 1979 to 2006 is characterized by high-frequency(i.e.,seasonal to interannual)temporal variability in SIE and zonal asymmetry in Sea Ice Concentration(SIC),which is primarily under the control of the Amundsen Sea Low(ASL).After 2007,however,sea ice changes exhibit a more spatially homogeneous pattern in SIC and a more temporally long-lasting mode in SIE.Further analysis reveals that sea ice-ocean interaction plays a major role in the low-frequency(i.e.,multiannual)variability of Antarctic sea ice from 2007−22.The related physical process is inferred to manifest as a strong coupling between the surface and the subsurface ocean layers,involving enhanced vertical convection and the downward delivery of the surface anomalies related to ice melting and freezing processes,thus maintaining the SIE anomalies for a longer time.Furthermore,this process mainly occurs in the Amundsen-Bellingshausen Sea(ABS)sector,and the weakened subsurface ocean stratification is the key factor triggering the coupling process in this region.We find that the Circumpolar Deep Water(CDW)over the ABS sector continued to shoal before 2007 and remained stable thereafter.It is speculated that the shoaling of the CDW may be a possible driver leading to the weakening of the subsurface stratification.
基金jointly supported by projects of the National Natural Science Foundation of China [grant numbers 42141017 and 41975112]。
文摘El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further investigation.To investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 models.The results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the future.The higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in variability.Carbon flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through temperature.This occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.
基金supported by the National Natural Science Foundation of China [grant number 42088101]。
文摘During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis results.To elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget analysis.The findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern Pacific.This increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective instability.Such a process is pivotal in amplifying intraseasonal convection anomalies.The observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.
文摘Maize is an important source of calories and protein in human lives in many countries of the world and is the main staple food in Africa, particularly in eastern Africa. In the Sudan, the low yield of maize was mainly due to the use of low yielding landraces. It is necessary to carry out breeding programs that deal with the production of high yielding, adaptable new varieties. Therefore, this study aimed to estimate genetic variability, heritability, genotypic performance and interrelationships among the traits. Ten maize genotypes evaluated at White Nile Research Station Farm, Kosti, of the Agricultural Research Corporation (ARC), Wad Medani Sudan were planted in a randomized complete block design with three replications during the two seasons of 2021 and 2022. Most evaluated genotypes exhibited a wide and significant variation in the 11 measured traits. Genotypic coefficient of variation and genetic advance were recorded for days to 50% tasseling, ear diameter (cm), number of grains per row and grain yield (t/ha) in both seasons. High heritability and genetic advance were recorded for grain yield, ear length, ear height, plant height, number of rows per ear, ear weight, days to 50% tasseling, 100-grain weight and days to 50% silking. Moreover, there was a highly significant and positive correlation of grain yield with number of rows per ear (r = 0.479), ear length (r = 0.381), 100-grain weight (r = 0.344) and days to 50% tasseling (r = 0.214). The highest yielding five genotypes across the seasons were TZCOM1/ZDPSYN (4.2 t/ha), EEPVAH-3 (4.2 t/ha), F2TWLY131228 (4.1 t/ha), PVA SYN6F2 (3.9 t/ha) and EEPVAH-9 (3.8 t/ha) these were needed to check the adaptability, stability and to test major maize growing areas to make sound recommendations for release.
基金The Fund of Laoshan Laboratory under contract No.LSKJ202202700the Basic Scientific Fund for National Public Research Institutes of China under contract No.2024Q02+1 种基金the National Natural Science Foundation of China under contract Nos 42076023 and 42430402the Global Change and Air-Sea InteractionⅡProject under contract No.GASI-01-ATP-STwin.
文摘The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole(IOD)events.The detailed processes of ENSO and/or IOD induced anomalies impacting on the ITF,however,are still not clear.In this study,this issue is investigated through causal relation,statistical,and dynamical analyses based on satellite observation.The results show that the driven mechanisms of ENSO on the ITF include two aspects.Firstly,the ENSO related wind field anomalies driven anomalous cyclonic ocean circulation in the western Pacific,and off equatorial upwelling Rossby waves propagating westward to arrive at the western boundary of the Pacific,both tend to induce negative sea surface height anomalies(SSHA)in the western Pacific,favoring ITF reduction since the develop of the El Niño through the following year.Secondly,the ENSO events modulate equatorial Indian Ocean zonal winds through Walker Circulation,which in turn trigger eastward propagating upwelling Kelvin waves and westward propagating downwelling Rossby waves.The Rossby waves are reflected into downwelling Kelvin waves,which then propagate eastward along the equator and the Sumatra-Java coast in the Indian Ocean.As a result,the wave dynamics tend to generate negative(positive)SSHA in the eastern Indian Ocean,and thus enhance(reduce)the ITF transport with time lag of 0-6 months(9-12 months),respectively.Under the IOD condition,the wave dynamics also tend to enhance the ITF in the positive IOD year,and reduce the ITF in the following year.
文摘Varietal deficiencies of upland rice lead to a low paddy grain yield. The aim of this study was to mutagenesis upland rice varieties to improve their agronomic performance. Seeds of varieties FKR45N and FKR47N were therefore irradiated with doses 300, 350 and 400 Gy. The irradiated seeds were sown and the panicles of the M1 plants were individually harvested, and then were advanced to M4 using the “one panicle - one progeny” method. The agronomic performance of M4 lines was compared to that of their parent. The gamma ray mutagenesis has induced significant variability in five yield components, i.e., plant height, main panicle length, total numbers of tillers and productive tillers and paddy grain yield between mutant lines. The highest variabilities were shown for the total number of tillers and the number of productive tillers as well as FKR45N (CV% = 40 % and 36%) and FKR47N (CV% = 31% and 30%) mutant lines. Principal component analysis led to rank the mutant lines from each variety in three clusters. The Pearson correlation showed that the paddy grain yield was significantly and positively correlated with the number of productive tillers (r = 0.61) and plant height (r = 0.66) for FKR47N mutant lines, and these correlation coefficients were r = 0.52 and r = 0.51 for FKR45N mutant lines, respectively. Gamma-ray irradiation also induced an earliness of 50% flowering of 62 days after sowing (DAS) in two FKR45N mutant lines and 67 DAS in one of KR47N mutant lines. The paddy grain yield was improved by 120% and 20% in two FKR45N and FKR47N mutant lines, respectively. A dwarf FKR45N mutant line with an early flowering of 67 DAS and a paddy grain yield (2.34 t ha−1) was generated. These results suggested that any positive increase in the six quantitative traits will increase the paddy grain yield.
文摘Introduction:Heart rate variability(HRV),defined as fluctuations in the time intervals between successive heartbeats,was generated by the sinoatrial node and modulated by the autonomic nervous system(ANS).HRV emerged as a prognostic marker in chronic heart failure(CHF),particularly for mortality risk assessment in Western countries.This study aimed to evaluate the utility of HRV measurement in the follow-up of CHF patients in a sub-Saharan African context.Methods:We conducted a cross-sectional,descriptive,and analytical study during six months,in the cardiology departments of the YaoundéGeneral Hospital(HGY)and the YaoundéCentral Hospital(HCY).Eligible participants were adults with a confirmed diagnosis of CHF based on clinical,echocardiographic and electrocardiographic criteria,who had been on treatment for at least three months and provided informed consent.Exclusion criteria included atrial disease,non-sinus rhythm(atrial fibrillation,atrial flutter),loss to follow-up,and death.Consecutive sampling was applied.HRV recordings were obtained twice at a two-month interval using a Polar H10^(®)heart rate monitor connected via Bluetooth to the Elite HRV application installed on an iPhone 12 Pro Max.SDNN was the standard deviation of all normal-to-normal(NN)intervals,and RMSSD was Root Mean Square of Successive Differences.HF(High Frequency,0.15-0.40 Hz)corresponds to respiratory sinus arrhythmia;R-R intervals were recorded at rest for 5 minutes.Treat ment adherence was assessed and its relationship to HRV was explored.Data were entered using CS Pro^(®)7.0 and analyzed with SPSS^(®)23.Results:Thirtyone patients were included,with a median age of 64 years;women accounted for 54.8%of the sample.The most prevalent cardiovascular risk factors were dyslipidemia(38.7%)and alcohol consumption(34.6%).The leading etiologies of CHF were hypertensive cardiomyopathy and dilated cardiomyopathy,each representing 54.8%of cases.Left ventricular failure was present in 74.2%,and 61.3%had a left ventricular ejection fraction(LVEF)<40%.The most commonly prescribed medications were ACE inhibitors(80.6%),beta-blockers(77.4%),and loop diuretics(77.4%).Non-adherence to treatment was reported in 45.2%(14/31)of participants.Patients with good adherence demonstrated significantly higher HRV indices at both time points,including SDNN[46.7(37.3-54.4)ms;p<0.050],RMSSD[58.6(49.5-78.9)ms;p<0.010],and HF power[708.2(417.2-1020.0)ms^(2);p=0.040].Factors associated with HRV impairment found a borderline association with BMI:overweight/obese patients tended to have higher odds of HRV impairment(OR=1.7,95%CI:0.4-7.4,p=0.052);age≤60 years(OR=0.8,95%CI:0.4-8.1,p<0.044)and Beta-blocker(OR=0.5,95%CI:0.1-2.5,p=0.030)use was associated with a lower risk of HRV alteration.Treatment with good adherence showed a significant association linked to a lower risk of HRV impairment(OR=0.2,95%CI:0.0-1.3).Conclusion:This study confirms the potential of HRV as a complementary tool for the follow-up of CHF patients.HRV indices,particularly regarding young age,good weight and combined with treatment adherence assessment,may provide a cost-effective,non-invasive method to improve CHF management in resource-limited settings.
基金Natural Science Foundation of Guangdong Province,China(2024A1515011352)National Natural Science Founda-tion of China(42275020)+2 种基金Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhu-hai)(311021001)Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies(2020B1212060025)Shanghai Frontiers Science Center of Atmosphere-Ocean Interaction(FDAOS-OP202401)。
文摘Utilizing the Standardized Precipitation Evapotranspiration Index(SPEI)and ERA5 reanalysis data,this study investigates the variability of spring drought in southern China from 1979 to 2022 and its associated drivers.The results indicate that southern China experienced interdecadal changes in SPEI over the past several decades,which can be concluded that drought severity intensified from 1979 to 2010,whereas a transition shift towards increased wetness occurred from 2010 to 2022.The first Empirical Orthogonal Function(EOF1)mode of SPEI variability in southern China accounts for 44.37%of the total variance,reflecting a uniform variation of SPEI across the region.In contrast,the second Empirical Orthogonal Function(EOF2),which explains 24.41%of the total variance,reveals a west-east dipole pattern in SPEI variability.Further analysis indicates that the positive phase of EOF1 is primarily driven by warm sea surface temperature anomalies(SSTAs)in the tropical eastern Pacific.These anomalies induce an anomalous anticyclone over the Philippine Sea,enhancing water vapor transport to southern China during spring.The positive phase of EOF2 is jointly influenced by warm SSTAs in the tropical Indian Ocean and the central Pacific;the latter induces anticyclonic anomalies over the Philippine Sea,which enhance water vapor transport from the western Pacific and increase precipitation in the eastern part of southern China.However,the warm SSTAs in the tropical Indian Ocean trigger an anomalous anticyclone over South Asia,inhibiting water vapor transport from the Bay of Bengal to the western part of southern China and thus reducing precipitation there.
文摘In this article,Deng and Song showed compelling evidence on the connection between heart rate variability(HRV)alterations and cancer in 127 cancer patients compared with healthy reference individuals,highlighting autonomic nervous system dysfunction as a significant physiological manifestation in cancer patients.We discussed that the reduced HRV may be associated with cancer treatments,e.g.,operation,chemotherapy and pain control and psychological response such as depression and anxiety related to the affected cancer.A management such as medicine to mood disturbances related to cancer has been shown a benefit to improve HRV in cancer patients.
基金financially supported by the National Natural Science Foundation of China(Grant No.51874207)the Natural Science Foundation of Shanxi Province(Grant Nos.202303021211042 and 202303011222006).
文摘This research employs micro-CT scanning technology to analyze the porosity,pore fractal dimension,and spatial variability of sandstone preheated to 600℃ and subsequently cooled in water at varying temperatures(20℃,60℃,100℃).The study investigates the mechanisms by which various factors influence thermal shock damage,focusing on the effects of cooling water temperature and the boiling phase transition.The objective is to develop a method for characterizing thermal shock damage that considers spatial variability.The findings indicate that thermal shock damage is limited to a shallow depth beneath the surface,with increased severity near the surface.The boiling phase transition significantly enhances the convective heat transfer coefficient,resulting in substantially higher thermal shock damage when cooled with 100℃ boiling water compared to 20℃ and 60℃ water.Furthermore,for the entire specimen,heating damage exceeds thermal shock damage,and the influence of thermal shock diminishes as specimen size increases.This study addresses the limitations of traditional methods for assessing thermal shock damage that disregard spatial variability and provides practical guidance for engineering projects to manage thermal shock damage more effectively.
基金supported by the Key Program of the Changji Prefecture Science and Technology Program(2023S04-10,2023S06-03).
文摘Purpose:To explore the clinical value of Electromyography(EMG)and Heart Rate Variability(HRV)in the diagnosis of early DPN and provide the basis for early diagnosis,treatment,and prevention of DPN.Methods:105 patients with type 2 diabetes mellitus(T2DM)in the Changji People’s Hospital were treated from January 2023 to December 2023.They were stratifi ed into DPN-symptomatic(DPN group,n=55)and DPN-asymptomatic(NDPN group,n=50)cohorts based on the presence or absence of clinically confi rmed diabetic peripheral neuropathy.The clinical biochemical indicators,nerve electromyography,and HRV parameters were obtained from electronic medical records,and diff erences in detection results were compared between the two groups.Logistic regression was applied to analyze the infl uencing factors of DPN in diabetes patients.The receiver operating characteristic(ROC)curve was applied to analyze the diagnostic value of EMG combined with other parameters for DPN.Results:From the results of the general information,diabetes duration,glycosylated hemoglobin(HbA1c),low-density lipoprotein cholesterol(LDL-C),total cholesterol(TC)and FBG in the DPN group were significantly differences compared with the NDPN group(p<0.05).There were no statistically significant differences in gender,age years,uric acid,and other general data(p>0.05).Compared with the NDPN group,the motor nerve conduction velocity(MNCV),sensory nerve conduction velocity(SNCV)of the ulnar nerve,median nerve,and tibial nerve in the DPN group were statistically signifi cant(p>0.05).The DPN group had higher average F wave latency and H wave latency in the tested nerve,with statistical signifi cance(p<0.05).HRV parameters decreased signifi cantly(SDNN,rMSSD,PNN50,and SDANN,all p<0.05).ROC analysis showed that the area under the ROC curve(AUC)of the combined diagnosis of DPN by duration of diabetes,HbA1c,EMG,and HRV was 0.897,the accuracy was 82.86%,the sensitivity was 78.00%,and the specifi city was 87.27%.The AUC of the combined diagnosis of the four parameters for DPN was signifi cantly higher than that of each alone(p<0.05).Conclusion:The combination of EMG and HRV has a high value in the assessment of DPN and can be used for early assessment of the extent of the lesion.
基金funded by the University of Science,VNU-HCM under grant number T2022-10 project entitled“Water level variability in the Mekong Delta under the impacts of anthropogenic and climatic factors”.
文摘In recent years,the water level in the Mekong Delta(MD)has undergone changes,attributed to the impacts of anthropogenic activities and climate change.Declining water levels have had implications for various aspects of life and aquatic ecosystems in the lower basin water bodies.Analyzing long-term trends in rainfall and water levels is crucial for enhancing our understanding.This study aims to examine the evolving patterns of water level and rainfall in the region.Data on water levels and rainfall from observation stations were gathered from the National Center for Hydrometeorological Forecasting,Vietnam,spanning from 2000 to 2014.The assessment of homogeneity and identification of trend changes were conducted using the Standard Normal Homogeneity Test(SNHT)and the Mann-Kendall test.The results indicate that changes in water levels at the Tan Chau and Chau Doc stations have been observed since 2010 due to the operation of flow-regulating structures in the upper Mekong River.Following the commencement of upstream dam operations,the water level at the headwater stations of the Mekong River has been higher than the long-term average during the dry season and lower than the average during the flood season.The study findings highlight the influence of altered rainfall patterns under the impact of climate variability(ICC)on water level trends in the study area.While rainfall plays a significant role in increasing water levels during the flood season,the operation of hydropower dams(UHDs)stands out as the primary factor driving water level reductions in the study area.
基金Supported by The Natural Science Foundation of Nanjing University of Chinese Medicine,No.XZR2021019The Outstanding Young Doctor Program of Jiangsu Province of Chinese Medicine,No.2023QB0140+1 种基金Project of National Clinical Research Base of Traditional Chinese Medicine in Jiangsu Province,No.JD2022SZ18The Natural Science Foundation of Nanjing University of Chinese Medicine,No.KYCX21_1710.
文摘BACKGROUND Heart rate variability(HRV)represents efferent vagus nerve activity,which is suggested to be related to fundamental mechanisms of tumorigenesis and to be a predictor of prognosis in various cancers.Therefore,this study hypothesized that HRV monitoring could predict perioperative complication(PC)in colorectal cancer(CRC)patients.AIM To investigate the prognostic value of HRV in hospitalized CRC patients.METHODS The observational studies included 87 patients who underwent CRC surgical procedures under enhanced recovery after surgery programs in a first-class hospital.The HRV parameters were compared between the PC group and the non PC(NPC)group from preoperative day 1 to postoperative day(Pod)3.In addition,inflammatory biomarkers and nutritional indicators were also analyzed.RESULTS The complication rate was 14.9%.HRV was markedly abnormal after surgery,especially in the PC group.The frequency-domain parameters(including pNN50)and time-domain parameters[including high-frequency(HF)]of HRV were significantly different between the two groups postoperatively.The pNN50 was significantly greater at Pod1 in the PC group than that in the NPC group and returned to baseline at Pod2,suggesting that patients with complications exhibited autonomic nerve dysfunction in the early postoperative period.In the PC group,HFs were also enhanced from Pod1 and were significantly higher than in the NPC group;inflammatory biomarkers were significantly elevated at Pod2 and Pod3;the levels of nutritional indicators were significantly lower at Pod1 and Pod2;and the white blood cell count was slightly elevated at Pod3.CONCLUSION HRV is independently associated with postoperative complications in patients with CRC.Abnormal HRV could predicted an increased risk of postoperative complications in CRC patients.Continuous HRV could be used to monitor complications in patients with CRC during the perioperative period.
基金supported by the National Natural Science Foundation of China(Grant Nos.42130604)the National Key Research and Development Program of China(Grant No.2023YFF0804704)+2 种基金the National Natural Science Foundation of China(Grant Nos.42105044)Swedish STINT(Grant No.CH2019-8377)the Priority Academic Program Development of Jiangsu Higher Education Institutions(Grant No.164320H116)。
文摘Since the mid-20th century,the Mongolian Plateau(MP)has experienced decadal droughts coupled with extreme heatwaves,severely affecting regional ecology and social development.However,the mechanisms behind these decadalscale compound heatwavedrought events remain debated.Here,using reconstructions and simulations from the Community Earth System Model Last Millennium Ensemble,we demonstrate that,over the last millennium,decadal droughts on the MP occurred under both warm and cold conditions,differing from recent compound heatwavedrought events.We found that by examining temperature changes during these drought periods,the distinct influences of external forcings and internal variability can be simply and effectively distinguished.Specifically,colddry events were primarily driven by volcanic eruptions that weakened the East Asian summer monsoon and midlatitude westerlies,reducing moisture transport to the MP.In contrast,warmdry events were predominantly induced by internal variability,notably the negative phase of the Atlantic Multidecadal Oscillation and the expansion of the Barents Sea ice extent.The recent extreme compound event was probably influenced by the combined effects of anthropogenic forcings and internal variability.These findings deepen our understanding of how external forcings and internal variability affect decadal drought events on the MP and highlight that recent compound events are unprecedented in the context of the last millennium.
基金jointly supported by the National Natural Science Foundation of China(Grant Nos.42422502,42275038)the China Meteorological Administration Climate Change Special Program(Grant No.QBZ202306)。
文摘Extensive flooding swept across large areas of Central Asia,mainly over Kazakhstan and southwestern Russia,from late March to April 2024.It was reported to be the worst flooding in the area in the past 70 years and caused widespread devastation to society and infrastructure.However,the drivers of this record-breaking flood remain unexplored.Here,we show that the record-breaking floods were contributed by both long-term climate warming and interannual variability,with multiple climatic drivers at play across the synoptic to seasonal timescales.First,the heavy snowmelt in March 2024 was associated with above-normal preceding winter snow accumulation.Second,extreme rainfall was at a record-high during March 2024,in line with its increasing trend under climate warming.Third,the snowmelt and extreme rainfall in March were compounded by record-high soil moisture conditions in the preceding winter,which was a result of interannual variability and related to excessive winter rainfall over Central Asia.As climate warming continues,the interplay between the increasing trend of extreme rainfall,interannual variations in soil moisture pre-conditions,as well as shifting timing and magnitudes of spring snowmelt,will further increase and complicate spring flooding risks.This is a growing and widespread challenge for the mid-to high-latitude regions.
文摘Climate variability significantly impacts agricultural water resources,particularly in regions like Vietnam's Plain of Reeds that heavily utilize rain-fed conditions.This study employs the FAO-AquaCrop model to estimate current and future irrigation water needs for rice cultivation in this critical subregion,aiming to identify optimal sowing schedules(OSS)that enhance rainwater utilization and reduce irrigation dependency.The model was driven by current climate data and future projections(2041-2070 and 2071-2099)derived from downscaled Global Circulation Models under RCP4.5 and RCP8.5 scenarios.The AquaCrop model demonstrated robust performance during validation and calibration,with d-values(0.82-0.93)and R²values(0.85-0.92)indicating strong predictive accuracy for rice yield.Simulation results for efficient irrigation water potential(IWP)under RCP4.5 revealed that strategic shifts in sowing dates can substantially alter water requirements;for instance,advancing the winter-spring sowing to December 5th decreased IWP by 15.6%in the 2041-2070 period,while delaying summer-autumn crop sowing to April 20th increased IWP by 48.6%due to greater reliance on irrigation as rainfall patterns shift.Similar dynamic responses were observed for the 2071-2099 period and for autumn-winter crops.These findings underscore that AquaCrop modeling can effectively predict future irrigation needs and that adjusting cultivation calendars presents a viable,low-cost adaptation strategy.This approach allows farmers in the Plain of Reeds to optimize rainwater use,thereby reducing dependency on supplementary irrigation and mitigating the adverse impacts of climate variability,contributing to more sustainable agricultural water management.
基金supported by the Natural Science Foundation of Beijing Municipality(No.8222004),Chinathe National Natural Science Foundation of China(No.51978019)+3 种基金the Natural Science Foundation of Henan Province(No.252300420445),Chinathe Doctoral Research Initiation Fund of Henan University of Science and Technology(No.4007/13480062),Chinathe Henan Postdoctoral Foundation(No.13554005),Chinathe Joint Fund of Science and Technology R&D Program of Henan Province(No.232103810082),China。
文摘Sandy cobble soil exhibits pronounced heterogeneity.The assessment of the uncertainty surrounding its properties is crucial for the analysis of settlement characteristics resulting from volume loss during shield tunnelling.In this study,a series of probabilistic analyses of surface and subsurface settlements was conducted considering the spatial variability of the friction angle and reference stiffness modulus,under different volumetric block proportions(Pv)and tunnel volume loss rates(ηt).The non-intrusive random finite difference method was used to investigate the probabilistic characteristics of maximum surface settlement,width of subsurface settlement trough,maximum subsurface settlement,and subsurface soil volume loss rate through Monte Carlo simulations.Additionally,a comparison between stochastic and deterministic analysis results is presented to underscore the significance of probabilistic analysis.Parametric analyses were subsequently conducted to investigate the impacts of the key input parameters in random fields on the settlement characteristics.The results indicate that scenarios with higher Pv or greaterηt result in a higher dispersion of stochastic analysis results.Neglecting the spatial variability of soil properties and relying solely on the mean values of material parameters for deterministic analysis may result in an underestimation of surface and subsurface settlements.From a probabilistic perspective,deterministic analysis alone may prove inadequate in accurately capturing the volumetric deformation mode of the soil above the tunnel crown,potentially affecting the prediction of subsurface settlement.
文摘Siberian taimen Hucho taimen(Pallas,1773)is a broadly distributed and popular sport fish with high economic value.However,low abundance and hard-to-reach habitat make the Siberian taimen a relatively understudied species.Here we describe the morphological variability of two size groups of Siberian taimen juveniles from the eastern(Amur River basin)and western(Kama River basin)parts of the species distribution.The largest morphological differentiation of Siberian taimen juveniles was observed at the inter-basin level.In the Amur River basin,Siberian taimen juveniles also differed morphologically even at sites located at a distance of 20 km from each other,which may be explained by a small home-range inhabitation of juveniles leading to the formation of their morphotype determined by local environmental conditions.The pattern of allometry varies in taimen from different rivers,which could be related to the ontogenetic shift of ecological niches and the level of heterogeneity of the river environment.
基金National Natural Science Foundation of China(42288101,42192564)Project of Ministry of Science and Technology of the People’s Republic of China(2020YFA0608802)Guangdong Major Project of Basic and Applied Basic Research(2020B0301030004)。
文摘El Niño is frequently followed by La Niña,while La Niña tends to sustain into the next year or even longer,exhibiting a notable phase transition asymmetry(TA)of El Niño-Southern Oscillation(ENSO).This study explores the potential influences of tropical Indian Ocean(TIO)decadal variability on TA based on a comparative analysis of the relationship between the TIO sea surface temperature anomalies(SSTA)and ENSO during different periods.Generally,the TIO SSTA strengthened TA before the 1980s,corresponding to a highly positive relationship between the whole TIO SSTA and ENSO.However,the weakening effect was exhibited after the 1980s when the correlation diminished.After the late 1990s,ENSO was only positively correlated with western TIO,with the westerly exhibit of the SSTA center leading to smaller impacts on TA.Moreover,TIO SSTA tends to weaken TA by promoting the transition efficiency of La Niña,while bringing little effect on that of El Niño.Physically,compared to the mid-1970s,TIO SSTA triggered westerly wind anomalies during the autumn and winter of the La Niña development phase in the central equatorial Pacific in the late 1990s,which sped up the decay of La Niña.It then regenerated westerly anomalies in the following winter,facilitating the development of El Niño.This study quantifies the impact of the TIO SSTA on TA in seasonal signals and investigates the decadal variability of such influence,aiming to further understand phase transition asymmetry and offer valuable insights for the prediction of multi-year La Niña.
文摘This study characterizes the instrumental record of California climate for the last 170 years.Our goal is to look for hydrologic variability at decadal and longer time scales that would be consistent with paleoclimate estimates of hydrologic variability in California for the last 3000 years.Our study focuses on meteorological summaries of annual precipitation and temperature.The precipitation records go back as far as 1850;the temperature records go back as far as 1880.California hydrologic records show strong variability at the interannual level due to ENSO forcing.They also all show a strong decadal(∼14 yr)cyclicity and evidence for multi-decadal to centennial variability that is consistent with California paleoclimate studies.California temperature records show a long-term warming of 5°F-6°F(2.8°C-3.4°C)associated with global warming,but there is no evidence for a similar long-term trend in hydrologic variability.Long-term Pacific Ocean variability adjacent to central and northern California,Pacific Decadal Oscillation(PDO)and North Pacific Gyre Oscillation(NPGO),show a similar decadal to centennial pattern of variability that we associate with our long-term hydrologic variability.The positive phase of the NPGO and the negative phase of the PDO are associated with the decadal scale(∼14 yr)dry cycles in California for the last 70 years.
